Biomedical Engineering Reference
In-Depth Information
3.1.2 l
IMItatIoNs
of
N
aNosysteMs
The following are limitations to the use of nanosystems:
1. Their small size and large surface area can lead to problems in formulation stabilities and
shelf life due to particle-particle aggregations, making the physical handling of nanopar-
ticles difficult in liquid and dry forms, and also resulting in limited drug loading and burst
releases (Mohanraj and Chen 2006).
2. Possible difficulties in drug incorporation and the achievement of desired releases (Jong
and Borm 2008).
3. Problems regarding biocompatibility, biodistribution, and targeting (Jong and Borm 2008);
4. A number of different classes of nanoparticles, with different physicochemical properties,
account for the adverse biological responses and produce safety and toxicological issues
(Parveen et al. 2012).
5. Possible adverse effects of residual materials after drug delivery (Jong and Borm 2008).
3.2 NANOPARTICLES: IMPORTANCE IN TODAY'S ERA
The current era has witnessed an unprecedented growth in the research and applications of nano-
technology. There is strong optimism that nanotechnology will bring significant advances in the
diagnosis and treatment of diseases. Nanotechnology has widespread applications in medicine,
including drug delivery, both
in vivo
and
in vitro
diagnostics, nutraceuticals, and the production of
improved biocompatible materials. Before the discovery of nanotechnology, healthcare was chal-
lenged by three interlocking crises that made healthcare systems unsustainable:
•
Rising costs
•
Changing demographics
•
Quality
Table 3.1 shows the scenario before the discovery of nanoparticles, about how life-threatening
diseases responded to therapy. For example, in the case of Alzheimer's disease and oncology, the
percentage responding to therapy was 30 and 25, respectively. This indicates a need of specialized
therapy, which can cure the diseases up to 90%.
TABLE 3.1
Outcome of the Old Model of R&D: Patient Response Rates to Major Drug Therapies
Category of Disease
% Who Respond to Therapy
Analgesic for pain (COX-2 inhibitors)
80
Asthma
60
Cardiac arrythmias
60
Schizophrenia
60
Migraine (acute)
52
Migraine (prophylaxis)
50
Rheumatoid arthritis
50
Osteoporosis
48
HCV
47
Alzheimer's disease
30
Oncology
25
